Analyst: Chevy Cruze could break U.S. diesel barrier

No official confirmation from General Motors yet of the report this week that it will field a diesel Chevrolet Cruze here in 2013, but both the car and timing are right.

"If they're going to do it, Cruze is the right car," says Jesse Toprak at researcher TrueCar.com. "Those are the buyers looking for value, and gas mileage is a big portion of value nowadays."

Cruze was the best-selling car in the U.S. in June, according to Autodata , and is No. 7 the first half of the year.

Only Volkswagen sells a significant number of U.S. diesels. Other mainstream makers have balked, thinking Americans hate diesels and seeing no business case for more expensive (than a gasoline car) diesel engines and needed anti-pollution gear -- despite diesels' higher fuel economy.

Honda and Nissan both have broken promises they made to launch diesels in the U.S.

The diesel Cruze -- GM sells it with a 2.0-liter turbo diesel outside the U.S. -- can get about a real-world 50 mpg on the highway. That should put it at 50 to 55 mpg in the test the government uses for its fuel-economy rules -- about a direct hit on the 52.6 mpg industry average the feds are considering by 2025.

That regulatory number is known as CAFE E., for corporate average fuel economy. It's now ramping up to 35.5 mpg by 2016. The rules use lab test mileage that's higher than the numbers on new car window stickers, which are adjusted down close to what people actually get on the road. The CAFE E number is for combined city/highway mileage.

Also slowing diesel intros here: Diesels go 20% to 40% farther on a gallon, but diesel fuel has been more expensive. The national average for gas is about $3.65 today, says AAA. Diesel is around $3.93.

Toprak figures modifying GM's Australian-market diesel Cruze to meet U.S. regulations would cost about $1,000 a car, but says GM easily could absorb that and keep the diesel model priced close to the gas version if it wants to get the diesel off to a fast start.

"They'll have to subsidize the vehicle slightly at first, but that's just like giving a small rebate, and in the long run it's worth it," Toprak says, if GM can "bring diesel to the masses."

Another plus for diesels is that they are "cheaper, and proven technology" compared with gas-electric hybrids, Toprak says.